Any ideas? this happens after I changed the water and nuts

well i would recommend you to make aDIary heere, so we have more numbers and facts to your grow. i just would wait until tomorrow i would say she just had some stress... but without more facts, its hard to say anything

Changed how? Did you just put in new solution at the same levels or you upped things? If everything is the same something is happening at the roots. Solution too hot/ cold? Did the airstone become disconnected? Are the O2 levels the plant needs surpassing what you are providing? Are there possible sediments that didn't get flushed out of your tank throwing things out of wack? Those are the things I would look at.